A position detecting device is known in the art, for example, as disclosed in Japanese Patent Publication No. 2007-132710. The position detecting device has a magnet provided in a movable member with a rectilinear travel and a magnetic detecting element movable relative to the magnet. The position detecting device detects a position of the movable member based on a signal outputted from the magnetic detecting element.
As shown in FIGS. 29A and 29B attached to the present application, the position detecting device of the above prior art (JP 2007-132710), has a magnet 100 and a magnetic detecting element 101 provided at a location separated from the magnet 100 in a magnetizing direction of the magnet 100. As indicated by dotted lines in FIGS. 29A and 29B, magnetic field of the magnet 100 is formed in a radial fashion. In a case an attachment position of the magnet 100 and/or the magnetic detecting element 101 is displaced, for example due to manufacturing tolerance, in a direction “X” perpendicular to a direction “Y” (a stroke direction) in which the magnet 100 moves, output characteristics of the magnetic detecting element 101 may be largely changed. This may cause a decrease of detection accuracy of the position detecting device.